Ukraine's top military spy says the country's troops appear close to stabilising the situation after Russia's ground attack into the Kharkiv region but has warned of a build-up of Russian forces to the north near the Sumy region.
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A cross-border attack on a new flank in Sumy region would likely stretch Ukraine's depleted defenders even further after Russia's incursion in the north of Kharkiv region opened a new front on Friday, forcing Ukraine to rush in reinforcements.
Russia has already made inroads into the north of Kharkiv region in two areas and said on Tuesday it had taken a 10th border village, Buhruvatka.
The police chief in Vovchansk, a town 5km from the border that has been the target of one of the main Russian thrusts, reported exchanges of fire in the north of the town.
Regional governor Oleh Syniehubov said two people had been killed on Tuesday in shelling there.
More than 7500 people from Vovchansk and nearby border areas had been relocated.
"For five days we never left the house, we didn't see anyone, we were so afraid to go out we never even opened the door," Natalia Yurchenko, who was moved from Vovchansk, told Reuters.
Apart from the devastation and the blow to Ukrainian morale in the region, home to Ukraine's second largest city of Kharkiv, the incursion is a distraction for defensive operations in the east where Russia has focused its offensive for months.
Military spy chief Kyrylo Budanov said Russia had already committed all the troops it had in the border areas for the Kharkiv operation but that it had other reserve forces that he expected to be used in the coming days.
"As of yesterday evening, a rapid trend towards a stabilisation of the situation had emerged - that is the enemy is, in principle, already blocked at the lines that it was able to reach," he said in televised comments.
Top Ukrainian officials say they do not believe Russia has the troop numbers to capture the city of Kharkiv.
Air strikes on residential areas of Kharkiv on Tuesday injured at least 20 people, local officials said.
One of the sites hit was a 20-storey building in the city centre, emergency services said.
Earlier, officials had said it was a 12-storey building.
Regional prosecutors said Russia had used its new guided UMPB D-30 bombs in that attack.
At another site, at least 15 garages near to a residential building caught fire after being struck by the guided bombs, the prosecutors added.
Ukrainian President Volodymyr Zelenskiy earlier accused Russia of seeking to reduce Kharkiv to rubble.
Budanov described the situation as fluid and rapidly changing, saying the "active phase" of the Russian operation was still ongoing.
Budanov said Russia had small groups of forces in the border areas near Ukraine's Sumy region in the vicinity of the Russian town of Sudzha from where Russian natural gas transits into Ukraine by pipe on its way to European customers.
"As for the Sumy region, the Russians actually planned an operation in the Sumy region from the very beginning ... but the situation did not allow them to take active actions and start the operation," he said.
The Russian assault is a test of Ukrainian manpower, which military analysts say is running short and needs to be replenished.
That shortfall is compounded by months of delays in US military aid, some of which Secretary of State Antony Blinken said during a trip to Kyiv on Tuesday had finally arrived, with more on the way that would "make a real difference".
Emil Kastehelmi, an open-source intelligence analyst with Black Bird Group, told Reuters the most important battle in the Russian push was taking place in Vovchansk, 45km from the city of Kharkiv.
"If Russia wants to go further south, Vovchansk needs to be captured. In this town, Ukraine is putting up a fight, and it seems that stronger Ukrainian defences are starting to appear around 6-8 km from the border in other places too," he said.
Tamaz Gambarashvili, head of Vovchansk's military administration, said in televised comments that the town was "almost destroyed".
"It's completely under (Ukraine's) control but there are small groups that try to enter the outskirts of the city, so there is a shooting battle," he said.
Australian Associated Press
